Test class for Batch Apex class that sends out emails in Salesforce

@isTest
public class EmailBatchClassTest {
    
    @isTest
    static void testEmailBatch() {
        // Step 1: Setup Test Data
        List<Contact> contacts = new List<Contact>();
        contacts.add(new Contact(LastName = 'Doe', Email = 'test@example.com'));
        insert contacts;
        
        // Create email message list to pass to batch
        List<Messaging.SingleEmailMessage> emailMessages = new List<Messaging.SingleEmailMessage>();
        
        for (Contact contact : contacts) {
            Messaging.SingleEmailMessage email = new Messaging.SingleEmailMessage();
            email.setToAddresses(new String[] { contact.Email });
            email.setSubject('Test Email');
            email.setPlainTextBody('Hello, this is a test email.');
            emailMessages.add(email);
        }

        // Step 2: Execute the Batch Job
        Test.startTest();
        EmailBatchClass emailBatch = new EmailBatchClass(emailMessages);
        Database.executeBatch(emailBatch, 1); // Batch size of 1 for simplicity
        Test.stopTest();

        // Step 3: Verify that emails were sent
        List<Messaging.SendEmailResult> results = [SELECT StatusCode, Success FROM AsyncApexJob WHERE JobType='BatchApex'];

        // Make assertions
        System.assertEquals(emailMessages.size(), results.size(), 'Expected number of emails to be sent.');
        for (Messaging.SendEmailResult result : results) {
            System.assert(result.isSuccess(), 'Expected email to be sent successfully.');
        }
    }
}